Glencore remains the only FTSE 100 company that does not have a woman on its board of directors. At the shareholder’s meeting at the start of this week, Chairman Tony Hayward promised that the company would remedy the situation by year’s end; but some big institutional investors have grown impatient, and UK business secretary Vince Cable said “it is simply not credible that one company cannot find any suitable women.”

The problem is industry-wide. A 2013 report by Amanda van Dyke (of Palisade Capital and Chair of the organization Women in Mining) and Stephney Dallmann (of PwC) found that mining companies “have the lowest number of women on boards of any listed industry group in the world.”

Maybe that doesn’t come as a great surprise to those familiar with mining, but within the industry there are companies who seem to be doing more than bluffing or hoping the issue will go away. Most of those are high profile global players. Women’s numbers decline steadily as we move down the ranks to the so-called juniors; and the likelihood that women will have a board seat or participate in a board committee also varies by territory. (South Africa leads the pack: over 21% of the committee seats of listed South African mining companies are occupied by women.)

Canada boasts the highest number of listed mining companies, and the “large mining companies in Canada are much further down the road [than smaller firms] in terms of their understanding of the importance of the role women play on boards.” The top-tier Canadian companies with high market capitalization (and the increased visibility that comes with size) have nearly 14% of board directorships held by women, but among the bottom 400 of the world’s top 500 miners, Canada has “the lowest participation on board committees by women, at 5.9%.”

The authors acknowledge that many of these companies are at early stages of development and they have only a few board seats to fill; but if they expect to grow and mature (as they do), there is no time like the present to lead or at least follow the lead of the big league players. When the same men keep winning the game of musical chairs — and when they sit next to each other (as they do) not just on one board, but on several, and their affiliations stretch back over decades — the result is likely to be not just over-familiarity but insularity, both of which are likely to impair and impede judgment. Meetings become a day at the club; the boardroom becomes an echo chamber.

As van Dyke and Dallmann note in a 2014 follow up report, it’s misleading to say, as many mining company executives do when pressed, that the small number of women directors correlates in a meaningful way with the lack of women with mining-related degrees. Only 32% of men on boards of mining companies have an engineering degree. So “there is no shortage of women in the talent pool;” according to van Dyke and Dallmann, “there is simply a perception of a lack of available female talent.”

This blinkered view of reality has real-world consequences, for shareholders and stakeholders in the communities where the miners operate. Mining companies with women on their boards see performance improvements on a number of fronts, from financial to social and environmental performance. “Sustainability” — as measured by water use, Bloomberg ESG score, UN Global Compact participation, Community Spend, and CSR or Sustainability Committee — improves across the board. For example, average total water use by mining companies “decreases steadily with an increase of women” in director roles — though it’s not entirely clear to me why that should be so — and “the amount [mining] companies spend on community projects and initiatives increases with the number of women on the board.” The authors are careful not to urge any hasty conclusions, but after surveying the data they are compelled to suggest that “the security of a company’s social licence to operate may be improved by having women on the board.”

I would go one step further: it’s difficult to countenance a mining company asking for social license to operate even as it deliberately insulates itself from social reality.